Posted
by
timothyon Thursday January 29, 2009 @06:12PM
from the teleport-a-child-and-we'll-be-impressed dept.

the4thdimension writes "While we may not be beaming up to the Enterprise anytime soon, a team of scientists from the University of Maryland and the University of Michigan have managed to teleport information between two atoms up to a meter apart. Until this point, only very tiny distances were able to be traveled. However, using a complicated system of photons, ions, lasers, and electromagnetics, scientists have managed to 'teleport' information contained on one atom to another atom that is in a separate sealed container. This can lead to a wide range of developments in computing and communications."Update: 01/29 22:29 GMT by T: Sorry, it's a dupe, but today's article in Time is better reading than the abstract anyhow.

They did not actually encode any information. They played a game of roll two dice and if I look at one, if I measure one, I can tell what the other must be. But I can't force the other to be anything I want, because I can't force the one I look at to be what I want, the measurement outcome, the result of "looking" is up to chance, so I can't store and encode arbitrary information as I need to. I can tell what's in the black box, but that's it.

I watched a BBC documentary 'Visions of the Future' online a couple of days ago, and a team in Vienna had already teleported information between photons years ago. See here [google.com], about 50 minutes in. (I recommend watching all three programmes, it's an interesting documentary). The professor in the video states that the record stands at 600 metres. I'm no physicist, so could someone explain what is so different about what has been achieved in the article? Is the difference between teleporting information between photons and atoms so distinct?

If you're talking about the existing product, the basis of "quantum" "cryptography" is shining a really dim light (or perhaps selling your product to a really dim bulb). There's more marketing buzzward than truth in both the "quantum" and the "cryptography", and further it doesn't actually solve any problems.

Of course, scifi quantum crypto is very cool, but then so is setting phasers on stun.

Well, every fiber network exchanges quanta of light. The thing is, the products sold as "quantum cryptography" don't use anything related to quantum mechanics to exchange data - no entangled particles or anything like that. That's the spin, but not the product. This product is a load of crap.

Engineer: We have eavesdroppers physically tapping our cables, can you help us?

Salesdroid: I have just the thing: Quantum Cryptography make eavesdropping impossible.

Yeah, if the attacker simply cannot be a man-in-the-middle on the "open" channel, he would gain nothing man-in-the-middle on the "quantum" channel. Better than nothing, I guess, but it would seem hard to arrange that in the real world, since the attacker is already inside your datacenter (or you don't need this in the first place). Hope no one invents a polarization-preserving photomultiplier!

Much like people feel that https is secure, when in the real world it's vulnerable to (demonstrated) attacks on th

In any case, I do agree that it's not worth the money. Not because it's snake oil but because non-quantum computing will probably never break RSA. And if it turns out that entangling qubits to each other is exponentially difficult, then RSA should be able to keep well ahead of those as well.

What about all the other phaser settings ?
"Limp,"
"Bit of a Cough,"
"Depression,"
"Bad Eyesight,"
"Ice Cream Van Nearby,"
"Sudden Interest In Botany,"
"Water In The Ear After Swimming,"
"Left The Oven On At Home."

Yeah it's new. It's the first time they've teleported quantum information between entangled atoms over this distance. I guess it's harder than doing it with photons due to... mass? Certainly it's not like you take the exact same setup you use to do photon teleportation, and it just works -- bamf! -- on atoms.

So it's nothing really 'new' in the sense that it's the same ol' teleporting-information-but-no-information-you-can-use trick just with a matter instead of energy. It's definitely something new in t

Yeah, it seems like every so often, there's another story in the media that "teleportation has been achieved," or "we can make things invisible," or "scientists have made light go faster than light." They go on to explain all the great things we could do if we could teleport things, go faster than light, and make things invisible.

Then, down near the bottom somewhere, they finally explain that no, we're not talking about real teleportation, but rather quantum entanglement that can't really be used for communication. We're not talking about real faster-than-light travel, but making a light wave that sort of looks like it's going faster than light but isn't. We're talking about something that might be useful for stealth airplanes, making them invisible to radar, and not real invisibility. Stuff like that.

And then they tag some throw-away line at the end like, "But who knows, maybe we'll be able to teleport to the moon next year!"

While I agree with you, it is one way of cathing the public's eye. Journalists want to make headlines, when they can't, they make up headlines remotely tangential to whatever material they've got.

My beef is with the Slashdot editors; when I started reading Slashdot, it was because the editors chose interesting stories. They still do, this is interesting, but they choose to present this particular mainstream article as the only link in their ingress as documentation and background inform

Then, down near the bottom somewhere, they finally explain that no, we're not talking about real teleportation

While I agree with the thrust of your complaint and share your hatred of journalists, I'm at least happy to see that both the recent/. stories on this have prominently featured the word "INFORMATION" as the 'thing' teleported. It still isn't quite correct, as 'information' in the ordinary sense of the term carries more ontological weight than 'quantum state' but it is a huge improvement over the u

In the past I've actually been far harder on scientists than journalists with regard to the use of "teleportation" as a term of art, which I consider to be misleading to the point of dishonesty.

But I have also seen too many cases where scientists have done their best to describe their work in fair terms only to see journalists (or their editors) mangle the resulting story almost beyond recognition. A colleague once came into work and said, "There were five stories in the scienc

...operate on A and measure it. Depending on the A measurement, apply one of two operations on B.

Doesn't that require a separate channel of communication, or am I misunderstanding? What I mean is, if you have to know A's state before you know what to do with B, then won't whoever measures A to then signal someone at B as to what operation to perform?

Not that I really understand your post, but it was my understanding that quantum entanglement couldn't be used for "communication" in the sense that people usually hope (faster than light communication).

No, it wouldn't be good for faster than light communication. But it could be used for secure communication, or implementing a "shift" register in a quantum computer. The separate line of communication doesn't pass information about the initial state of A, just its final measurement, which actually says nothing about it's initial state to anyone or anything except ion B. And, because we're talking about quantum mechanics, A's initial quantum state could be a superposition of states, not just "0" or "1".

When I said, "can't really be used for communication," I was trying to refer to faster-than-light communication. It seems to me when most people talk about "teleportation," the first hope is to actually deconstruct a physical object in one place while instantaneously reconstructing it in another. Then when it's explained that "no, we're talking about quantum entanglement and teleporting information," the hope usually turns into the idea that you would alter the state of one entangled particle in a

Kind of blows the whole concept of bandwidth out of the water, doesn't it? When you can instantly duplicate bits of information to a machine at any location...

"Oh my gosh, you solved their problem. They can achieve 90%, you only need to implement an error correcting algorithm capable of handling 10% of error, and you have achieved instant information transmission!".No, really, I find their results intriguing, but that was not my point at all:)

Only in the common three spatial dimensions. They're pretty much right on top of each other in the 5th and 6th dimensions, which results in all kinds of practical jokes going on between their physics departments.

i see one problem with this 1 lightyear = 9.4605284 Ã-- 1015 meters and the technology used to tell scientists have if this was "teloported" have to take a measure of a unit of time that is so small my calculator (the one that comes with windows) and my TI-84-SE can't calculate how small it is. how can we say it has "teloported" if we can't measure the time it takes to get from point A to point B if the smallest measure of time we have is greater then the time it takes get from point A to point B

Teleportation at the speed of light would take 3.3 ns (3.3e-9 seconds) to cover a distance of 1m. This is certainly measurable.
However no time difference has been measured in this experiment because the teleportation is instantaneous.

I can recognize your words individually, but they appear to me to make no sense whatsoever.

Specifically, what is this "instantaneous" of which you speak? You seem to be saying that two events happen at the same time but in different places.

Unless you want to throw out the entire theory of relativity, you mean one of two things. Either you mean that they happen at the same time in some certain reference frame, or you mean the events have spacelike separation and nothing more.

One of the thoughts that's crossed my mind as we further explore and understand utilization of quantum information is that if there is sentient beings "Out There" with some level of capability for space exploration is that it would seem that this would be a very likely way for them to maintain communication. Efforts such as SETI would then be attempting to discover background noise (I use the term "noise" here more as commentary on what most of what we communicate tends to be)of civilizations no more advanc